Jig clamp



Patented Sept. 4, 1945 umrl-zbffsrA'res PATE:Nrj-fn t0, Edward G. BuddManufacturing Company, Philadelphia, Pa., a corporation of PennsylvaniaApplication September 10, 1943, Serial N o. 501,846

. i 4 Claims. This invention relates to al iig clamp, suc-h as thatwhich may be used to clamp one or more angle-flangedv stringers orchords to a web for riveting or'welding the parts together, andliasfor'an object the provision of improvements in this art.

One of the particular objects of the invention is to provide a vclamp ofconvenient type for holding edge reinforcing strips having overhanging`flanges to a web or body member' tov whichthey are to be secured.

Another object is to provide a clamp which may be quickly engaged withthe stock.

Another object is to provide a clamp which will accurately place andsecurely hold the stock.

Another'object is to provide a clamp of simple and inexpensive design.

The above and other objects and advantages will be evident from thefollowing description of an exemplary'embodiment of the invention,reference being made to the accompanying drawing, wherein: Y

Fig. 1 is a side elevation and section of the clamp in stock grippingposition;

Fig. 2 is a horizontal section taken on the line 2 2 of Fig. 1;

Fig. 3 is a partial vertical transverse section taken on the line 3-3 ofFig. l; and

Fig. 4 is a side elevation showing the clamp in released position.

Say the structure to be secured together is the rib, spar, or otherframe member of an airplane, it may comprise a web l and one or morestringers, chords, or cap strips Il. When these chords are simple angle0r flanged members, they may be readily clamped to the Web by simple jigclamps of -well-known construction. Even when there is a chord memberwith an overhanging flange, that is, an edge iiange which turns back inthe direction away from the main flange, the usual type of clamp may beused if the chord member is on the top side where it is readily visibleand accessible. In such a case the web may be laid on a fixed rest orpositioning member; the flanged chord member laid on the web; and aswinging overhanging clamp brought over, down and back to enter beneaththe overhanging flange and clamp the parts in proper position.

But when the chord member with overhanging flange is to be placedbeneath the web where it is diiicult to locate and position, the clampof the present invention provides a convenient means for quicklybringing the parts into proper position.

The clamp here illustrated comprises a frame l5 having a base I6 andl a"pedestal` l1.' The base is adapted to b'essecurecll to a table orstand(notshown) which carries other 'such'clamps and also lsuitable xedpartsy or rests to support the stock parts at proper height.

The lower chord memberl is engaged by a rest jaw having" an overhang 2i,the rest jaw being mounted-rigidly ,on/a slide or'slides`22're'-ciprocable in arguid'epr guides 2*3- onthe pedestal Il. Theuppefsurfacev 2li-of the 'rest is at the properfheightgto support theange yof the chordV member which is, parallel "to the web This upperAsurface *moves back and" forth ina horizontal 4plane and when vtherestfjaw is pulled back the: overhang '2|'V enters!! the space.

within the Chord-member to engagethe-vertical* flange. The rangeofmovement i's- Asuch that the'ehord member ismoved back'to propersition when the rest'jaw 4movesffback and Vthat the overhang 2| clears"the overhan'ging ange l2 of' the rchord member when the'rersthjaw isreturned toits ,forwardy position.

The 'rear 'end of the slide 22 "is secured to a car# riage 26 which ismoved in one or both directions (here both) by a cam 21 mounted in thecarriage upon a shaft or shaft stubs 28 and turned by a handle 29between fixed abutments 30 and 3l. These abutments are carried by thepedestal and may consist of hardened blocks anchored in position byscrews or the like.

'To the upper part of the carriage there is hinged, as by a pivot pin32, a swingable bar 33 carrying a clamp jaw 34. The jaw is rigid withthe -bar and has an overhang 35 adapted to enter the space within theupper chord member. The clamp jaw moves back and forth with the lowerreet jaw and in addition may be swung out of p0- sition to permit thestock members to be introduced to and removed from the jig.

The clamp jaw 34 has a clamp face 36 on its lower side which presses thestock members together when the jaws are pulled back by the eccentric.The means by which this clamping action is effected is a wedging devicecomprising a pin 38 on the jaw bar 33 and a tapered slotl 39 for the pinformed in an upstanding bracket 40 secured to the pedestal I1.

In operation, when the handle and eccentric are turned in one directionthe jaws are moved rearwardly and clamped upon the stock, the upperclamp ljaw and bar, of course, first having been swung over into stockengaging position; and when the handle and eccentric are moved in theother direction ythe jaws are moved forwardly to the invention providesa simple, convenient and eective device for clamping vand holding anumber of stock members of shapes which are difficult to clamp rapidlyby usual clamping devices.V

While one embodiment of the invention has been illustrated and describedby way of example, it is to be understood that-there may be variousembodiments within the limits of the prior art andthe scope of thesubjoined claims.Y

What is claimed is: 1. A stock clamp adapted to position and clamp anoverlying chord member having an overhangl ing iiange upon a bodymember, comprising in combination, a iiXed jaw, a first clamping jawmounted for simple reciprocatory movement in the plane of the bodymember toward and from the iixed jaw, a second clamping jaw mounted forreciprocatory movement in the plane of the body member toward and fromthe xed jaw and also for swinging movement to clear the space above therst clamping jaw on the side of the body member in unclamped position,means for reciprocating said clamping jaws, and means for bringing saidclamping :laws toward each other as they approach the xed jaw.

2. A stock clamp adapted to position and clamp an overlying chord memberhaving an overhang- Y ing Vflange upon a body member, comprising incombination, a Vfixed jaw, a first clampingV jaw mounted' for simplereciprocatory4 movement in the plane ofthe body member toward and fromthe iixed jaw, a, second clamping jaw mounted for reciprocatory movementin the plane of the bodyl member toward and from the xed jaw and alsobeing pivoted for freeoutward swinging movement by hand about a pivotbehind the region of the body member to clear the space above the rstclamping jaw in unclamped position, means for reciprocating saidclamping jaws abreast, and

Y position.

means for moving the second clamping jaw toward the rst clamping jaw to'clamp the members as the jaws approach their final rearward position.

3. A stock clamp adapted to position and clamp angle-section chordmembers having return angesruponthe opposite sidesrof a plate member,comprising'in combination, a rearstop, a first jaw mounted forVreciprocation toward and Vfrom said rear stop, said rst jaw having aside face forming an aligning support for the lower chord member, andsaid rst jaw also having a rear overhang with a rear face adapted to fitwithin and press the lower chord member against Ysaid rear stop, asecond jaw mounted for reciprocation toward and from said rear stop,said second jaw being mounted to swing out freely about a rear pivot topermit insertion of the chord and plate members in a direction normal tothe aligning face of lthe rst jaw and in front of the rear stop, saidsecondjaw` having an aligning face parallel with the aligning face ofthe first jaw when inV stock eng-agingposition Vand an overhanging rearface adapted to fit within and press the upper chord member against saidrear stop, means to reciprocate said jaws together to clamp the stockagainst the rear stop, and means for moving the second jaw Vtoward therstr to clamp the stock between them as the Yjaws near their rearposition'.V Y

4. A stock clamp comprising in combination, a rear-fixed jaw,a pair ofclamping jaws reciprocable toward vand from said iixed jaw to clampstock thereagainst, one of said clamping jaws having straightreciprocation to guide the stock and the other clamping jaw beingmounted to swing freely outward when in the unclamped position away fromthexed jaw, means for reciprocating saidV clampingjaws, and means formov-V ingY the swinging jaw against the stock and toward the firstclamping jaw as the clamping jaws move toward the xed jaw and the finalclamped THOMAS EARLE YEAGER.

